U.S. patent number 10,080,549 [Application Number 15/015,188] was granted by the patent office on 2018-09-25 for echogenic nerve block apparatus and system.
This patent grant is currently assigned to Avent, Inc.. The grantee listed for this patent is Avent, Inc.. Invention is credited to Dominic J. Cooke, Siddharth Desai, Steve S. Khalaj, Roger Dillard Massengale.
United States Patent |
10,080,549 |
Massengale , et al. |
September 25, 2018 |
Echogenic nerve block apparatus and system
Abstract
An apparatus for performing a nerve block procedure, the
apparatus being composed of an echogenic needle or an echogenic
soft tissue tunneling device and an echogenic catheter configured
for controlled delivery of a medication. The apparatus may further
include a sheath such that at least one of the needle or tunneling
device and sheath is echogenic. The present invention also
encompasses a system for performing a nerve block procedure, the
system includes introducing an echogenic needle in the general area
of a nerve bundle, positioning the echogenic needle adjacent the
nerve bundle utilizing sonic imaging techniques, introducing an
echogenic catheter configured for controlled delivery of a fluid
through the echogenic needle, withdrawing the echogenic needle,
positioning the echogenic catheter adjacent the nerve bundle
utilizing sonic imaging techniques, and delivering fluid to the
nerve bundle through the echogenic catheter.
Inventors: |
Massengale; Roger Dillard
(Mission Viejo, CA), Khalaj; Steve S. (Laguna Hills, CA),
Desai; Siddharth (Ladera Ranch, CA), Cooke; Dominic J.
(Mission Viejo, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Avent, Inc. |
Alpharetta |
GA |
US |
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Assignee: |
Avent, Inc. (Alpharetta,
GA)
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Family
ID: |
45934739 |
Appl.
No.: |
15/015,188 |
Filed: |
February 4, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20160151049 A1 |
Jun 2, 2016 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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13272643 |
Oct 13, 2011 |
9254146 |
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61394040 |
Oct 18, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B
8/481 (20130101); A61B 17/3401 (20130101); A61M
19/00 (20130101); A61M 25/0108 (20130101); A61B
8/0841 (20130101); A61M 5/3286 (20130101); A61M
5/3291 (20130101); A61B 2090/3925 (20160201); A61B
2090/3929 (20160201); A61B 2017/3413 (20130101) |
Current International
Class: |
A61B
8/08 (20060101); A61M 25/01 (20060101); A61B
17/34 (20060101); A61M 19/00 (20060101); A61M
5/32 (20060101); A61B 90/00 (20160101) |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Office Action--Russian Patent Office, dated Jul. 30, 2015. cited by
applicant .
Translation of Office Action--Japanese Patent Office, dated Aug.
18, 2015. cited by applicant.
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Primary Examiner: Stigell; Theodore
Attorney, Agent or Firm: Dority & Manning, P.A.
Parent Case Text
The present application is a Divisional Application of U.S.
application Ser. No. 13/272,643, filed on Oct. 13, 2011, and issued
as U.S. Pat. No. 9,254,146, which claims the benefit of priority
from U.S. Provisional Application No. 61/394,040 filed on Oct. 18,
2010, the contents of which are incorporated herein by reference.
Claims
What is claimed is:
1. An apparatus for performing a nerve block procedure, the
apparatus comprising: an echogenic needle and an echogenic catheter
insertable through the echogenic needle, the echogenic catheter
configured for controlled delivery of a medication, the echogenic
catheter comprising an elongated tubular member having walls and an
echogenic catheter tip, the elongated tubular member comprising a
plurality of exit holes or slots in a portion thereof and an
elongated porous member residing within the walls, the echogenic
catheter tip comprising a support that resides within the elongated
tubular member, the support comprising a shape that reflects an
effective amount of acoustic waves such that the echogenic catheter
tip is satisfactorily visible during sonic imaging, the shape being
selected from gear shapes, hourglass shapes, hemisphere-terminated
cylinder shapes, and multi-faceted geometric shapes formed by
interlocking polygons, the support comprising edges that engage the
walls of the tubular member to prevent the echogenic catheter tip
from moving relative to the elongated tubular member, wherein the
edges and the walls of the tubular member, when engaged, define a
plurality of grooves or notches between the edges and the walls of
the tubular member.
2. The apparatus of claim 1, wherein the elongated tubular member
of the catheter is also echogenic.
3. The apparatus of claim 1, wherein the elongated porous member is
constructed of or incorporates a material that increases its
acoustic impedance.
4. The apparatus of claim 1, further comprising an echogenic
sheath.
5. An echogenic catheter configured for controlled delivery of a
fluid across an anatomical region, the echogenic catheter
comprising: an elongated tubular member having walls, the elongated
tubular member comprising a plurality of exit holes or slots in a
portion thereof, and an elongated porous member residing within the
walls; and an echogenic catheter tip comprising a support that
resides within the tubular member, the support comprising a shape
that reflects an effective amount of acoustic waves so the tip is
satisfactorily visible during sonic imaging, the shape being
selected from gear shapes, hourglass shapes, hemisphere-terminated
cylinder shapes, and multi-faceted geometric shapes formed by
interlocking polygons, the support having edges that engage the
walls of the tubular member to prevent the tip from moving relative
to the elongated tubular member, wherein the edges and the walls of
the tubular member, when engaged, define a plurality of grooves or
notches between the edges and the walls of the tubular member.
6. The echogenic catheter of claim 5, wherein the elongated tubular
member of the catheter is also echogenic.
7. The echogenic catheter of claim 5, wherein the elongated porous
member is constructed of or incorporates a material that increases
its acoustic impedance.
Description
FIELD OF THE INVENTION
This invention relates to pain management systems, and more
specifically to catheter-based infusion systems for the
administration of fluids. Most specifically, this invention relates
to an apparatus and system for performing a nerve block
procedure.
BACKGROUND OF THE INVENTION
Prior to performing a surgical operation on a part of the body,
such as for example the arms or legs, it may be desirable to
perform a nerve block in order to anesthetize a nerve bundle in a
part of the body proximate to where surgery will occur. Often, a
catheter-based infusion system is utilized to both block the nerve
bundle for surgery and to provide a continuous, low flow rate of
the anesthetic over a period of time (e.g., 2-3 days following
surgery) for post-operative pain management.
One approach is to introduce an epidural-type needle or needle and
peel-away-type sheath into the general area of the desired nerve
bundle. Once proper location of the needle is achieved, a test dose
of the anesthetic may be provided through the epidural needle and a
catheter may be introduced through the needle to administer the
anesthetic and maintain the nerve block.
Several methods of targeting needle location exist today--insulated
needles having an integral conductive wire such that a small amount
of current may be pulsed through the needle or catheter by a nerve
stimulator (i.e., a current generator). An electrical current of
0.1 to about 2 mA will induce motor movement in the patient when
the tip of the needle (frequently called a "stimulating needle") is
near the nerve. When the stimulating needle is probed into the
general area of the desired nerve bundle, the pulsing current
stimulates the nerve and causes a motor response to assist in
properly locating the needle. As the current is reduced, the motor
effect is also reduced so a needle that causes movement at a low
current is likely to be very close to the desired area for drug
delivery.
One problem with this approach is that the catheter insertion
through the needle may move the tip of the needle away from the
target zone. Alternatively and/or additionally, the tip of the
catheter may curl away from the target zone during insertion.
Several manufacturers have designed stimulating catheters that
correct this problem by passing the current first through the
needle and then separately through the catheter. The problem with
this is that the catheter cannot be steered to the target zone
without risking pulling back through the needle and potentially
damaging the catheter. In addition, the additional time needle to
place and maneuver the catheter is significant and after the
catheter is secured, it can dislodge by patient movement and then
become ineffective.
Ultrasound guided techniques have added imaging to the procedure,
but they are mainly used to see the adjacent vessels and are not
always good at seeing the needle and/or catheter. The problem with
ultrasound guided techniques is that the needle and catheter cannot
be easily seen through tissue. That is, the ability to see the tip
and/or other portions of the needle and/or catheter under
ultrasound imaging techniques is limited. Another problem is that
conventional catheters do not allow one to place the catheter
quickly allowing for some small migration or tip mis-positioning
while still delivering drug to the target area.
A variety of approaches have been used to enhance ultrasonic
imaging of medical devices by increasing the acoustic reflection
coefficient of the devices. In U.S. Pat. No. 4,401,124 issued to
Guess et al., the reflection coefficient of a biopsy needle is
enhanced by the use of a diffraction grating disposed on the
surface of the needle. A variety of mechanisms for enhancing the
ultrasound image of a portion of a medical instrument are also
disclosed in U.S. Pat. No. 5,289,831 issued to Bosley, U.S. Pat.
No. 5,201,314 issued to Bosley et al. and U.S. Pat. No. 5,081,997,
also issued to Bosley et al. These patents disclose catheters and
other devices provided with echogenic surfaces including spherical
indentations or projections in the range of 0.5 to 100 microns or
fabricated of material incorporating glass spheres or high density
metal particles in the range of 0.5 to 100 microns. The use of
micro-bubbles introduced into polymers to provide echogenic
catheter components is described in U.S. Pat. No. 5,327,891, issued
to Rammler.
However, these features add complexity to manufacturing and may
negatively impact the performance of a catheter having a plurality
of exit holes along a portion of the catheter. For example, glass
beads adhered to the exterior of a catheter may become dislodged.
Glass beads incorporated into the polymer matrix may create
difficulties during creation of exit holes. Microbubbles formed in
the polymer matrix of the catheter wall can be difficult to form
reliably during the extrusion process. Spherical indentations or
spherical protuberances can be challenging and/or expensive to form
on a single use item. For example, an EchoTip.RTM. Ultrasound
Needle has a plurality of spherical indentations that can increase
acoustic reflection. However, these spherical indentations can be
difficult or expensive to produce in a metal needle and may be
ineffective when implemented in items that are generally not very
acoustically reflective such as, for example, a polymer
catheter.
SUMMARY OF THE INVENTION
The present invention addresses these problems by providing an
apparatus for performing a nerve block procedure, the apparatus
being composed of an echogenic needle and an echogenic catheter
configured for controlled delivery of a medication.
The present invention also encompasses a system for performing a
nerve block procedure, the system includes introducing an echogenic
needle in the general area of a nerve bundle, positioning the
echogenic needle adjacent the nerve bundle utilizing sonic imaging
techniques, introducing an echogenic catheter configured for
controlled delivery of a fluid through the echogenic needle,
withdrawing the echogenic needle, positioning the echogenic
catheter adjacent the nerve bundle utilizing sonic imaging
techniques, and delivering fluid to the nerve bundle through the
echogenic catheter.
An aspect of the present invention encompasses addresses an
echogenic needle configured for placement into the body adjacent a
nerve bundle. The echogenic needle has a distal end composed of an
echogenic needle tip, a hollow needle body, and a proximal end that
includes a fitting. The needle body may be an echogenic needle
body.
Generally speaking, the echogenic needle tip may be formed from
cobalt chromium (also referred to as "cobalt chrome"), glass or
other material having a high degree of acoustic impedance.
Alternatively and/or additionally, the echogenic needle tip may
have a shape or spatial configuration that reflects an effective
amount of acoustic waves so the tip is satisfactorily visible
during sonic imaging. Suitable shapes for the echogenic needle tip
include beveled, generally planar surfaces. Alternatively and/or
additionally, grooves and/or indentations may be added to the
needle.
The needle tip and/or the needle body may be rendered echogenic by
coating the needle tip and/or a surface of the needle body with a
material that increases acoustic impedance. Exemplary materials
include titanium carbide, titanium nitride, titanium aluminum
nitride, titanium aluminum carbon nitride and similar materials.
Hard, dense, amorphous non-crystalline solids such as glass,
acrylic glass--also referred to as poly(methyl methacrylate), and
hard, glassy hydrogels such as those described in US Patent
Application Publication No. US 2006/0141186 may also be used. The
needle tip and/or needle body may be rendered echogenic by coating
the needle tip and/or a surface of the needle body with various
known echogenic coatings.
Another aspect of the present invention encompasses an echogenic
catheter configured for controlled delivery of a fluid across an
anatomical region. The echogenic catheter is composed of an
elongated tubular member and an echogenic catheter tip. The
elongated tubular member may be an elongated tube with a plurality
of exit holes or slots in a portion of the elongated tube, and an
elongated porous member residing within the tube. Alternatively,
the elongated tubular member may be made of a porous membrane such
as a filtration membrane. Exemplary filtration membranes may be
made of polytetrafluoroethylene.
The echogenic catheter tip may be a portion of a distal end of the
catheter formed from cobalt chrome, glass, or other material having
a high degree of acoustic impedance. Alternatively and/or
additionally, the echogenic catheter tip may be or may include an
echogenic insert or plug formed from or coated with cobalt chrome,
glass, or other material having a high degree of acoustic
impedance. The echogenic catheter tip, insert or plug may have a
shape or spatial configuration that reflects an effective amount of
acoustic waves so the tip is satisfactorily visible during sonic
imaging. Suitable shapes include gear shapes (e.g., circular or
cylindrical shapes having grooves, notches and/or crenulations that
provide a plurality of flat reflective surfaces), spherical shapes,
multi-faceted geometric shapes formed by interlocking polygons
(e.g., a geodesic dome shape). Sharp and/or flat edges of the
echogenic insert may engage the walls of the lumen defined by the
catheter body to prevent the echogenic insert from moving relative
to the elongated tubular member.
The elongated tubular member of the catheter (and/or the catheter
tip) may be rendered echogenic by coating an internal or external
surface with a material that increases its acoustic impedance.
Exemplary materials include titanium carbide, titanium nitride,
titanium aluminum nitride, titanium aluminum carbon nitride and
similar materials. Hard, dense, amorphous non-crystalline solids
such as glass, acrylic glass--also referred to as poly(methyl
methacrylate, and hard, glassy hydrogels such as those described in
US Patent Application Publication No. US 2006/0141186 may also be
used. The elongated tubular member (and/or the catheter tip) may be
rendered echogenic by coating it with various known echogenic
coatings.
The coating may be on the outside of the elongated tubular member
or the coating may be located on the interior of the elongated
tubular member. In some aspects of the invention, the coating on
the interior of the elongated tubular member may be a coating that
incorporates acoustically reflective particles in a carrier. For
example, the coating may include spherical beads of glass or other
acoustically reflective material in a carrier that binds spherical
beads to an internal surface of the elongated tubular member.
According to another aspect of the invention, the elongated tubular
member of the catheter may be rendered echogenic by including an
internal component that increases its acoustic impedance. The
internal component may be an elongated tubular coil spring enclosed
within the tubular member. The elongated tubular coil spring may be
may formed from an echogenic material, may be coated with a
material that increases its acoustic impedance, or may have a
surface that is modified with grooves, diffraction gratings,
flattened portions, dimples or the like to increase its acoustic
impedance. Alternatively and/or additionally, the internal
component may be a component that actively generates acoustic waves
that are visible during sonic imaging. Such a component may include
an energy source and a transducer such as, for example a
piezoelectric transducer that converts the energy into acoustic
waves.
In embodiments where the elongated tubular member is an elongated
tube with a plurality of exit holes or slots in a portion of the
elongated tube and an elongated porous member resides within the
tube, it is contemplated that the elongated porous member may be
made of or may include material that increases its acoustic
impedance.
Other objects, advantages and applications of the present
disclosure will be made clear by the following detailed description
of a preferred embodiment of the disclosure and the accompanying
drawings wherein reference numerals refer to like or equivalent
structures.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of an exemplary echogenic needle.
FIGS. 2A to 2D are illustrations of illustrated exemplary shapes
for increasing the acoustic impedance of a needle tip.
FIG. 3 is an illustration of cross-section of the exemplary
echogenic needle of FIG. 1 taken across line A-A.
FIG. 4 is an illustration of an exemplary echogenic catheter.
FIG. 5 is an illustration of cross-section of the exemplary
echogenic catheter of FIG. 4 taken across line B-B.
FIG. 6 is an illustration of a detail of an exemplary echogenic
catheter showing an exemplary echogenic catheter tip.
FIG. 7 is an illustration of a detail of an exemplary echogenic
catheter including an exemplary echogenic catheter tip.
FIG. 8 is an illustration of a detail of an exemplary echogenic
catheter showing an exemplary echogenic insert or plug.
FIG. 9 is an illustration of a cross-section of the exemplary
echogenic catheter of FIG. 8 taken across line C-C.
FIG. 10 is an illustration of an exemplary echogenic catheter
tip.
FIG. 11 is an illustration of a cross-section of an exemplary
echogenic catheter showing an exemplary echogenic insert or
plug.
FIG. 12A is an illustration of an exemplary echogenic catheter
tip.
FIG. 12B is an illustration of an exemplary echogenic catheter
tip.
FIG. 12C is an illustration of an exemplary echogenic catheter
tip.
FIG. 13A is an illustration of an exemplary echogenic catheter
showing an exemplary echogenic insert or plug.
FIG. 13B is an illustration of a cross-section of the exemplary
echogenic catheter of FIG. 13A taken across line D-D.
FIG. 14A is an illustration of an exemplary echogenic catheter
incorporating an exemplary echogenic bead.
FIG. 14B is an illustration showing a detail of an exemplary
echogenic bead from FIG. 14A.
FIG. 15A is an illustration of an exemplary echogenic catheter
incorporating voids or bubbles in the catheter.
FIG. 15B is an illustration showing a detail of the echogenic
catheter from FIG. 15A.
FIG. 16A is an illustration of an exemplary echogenic catheter
incorporating a catheter having an elongated shaft.
FIG. 16B is an illustration showing a detail of the echogenic
catheter from FIG. 16A.
FIGS. 17A to 17C are illustrations of an exemplary echogenic
catheter incorporating a spring.
FIG. 18 is an illustration of an exemplary echogenic catheter
incorporating a guide wire.
FIG. 19 is an illustration of an exemplary echogenic catheter
incorporating a metal band.
FIG. 20 is an illustration showing a cross-section of the catheter
incorporating a metal band from FIG. 19.
DETAILED DESCRIPTION
FIGS. 1-3 illustrate aspects of an exemplary echogenic needle
configured for placement into the body adjacent a nerve bundle.
Referring to FIG. 1 the echogenic needle 10 has a distal end 12
composed of an echogenic needle tip 14 that may terminate in a
beveled aperture having include beveled, generally planar surfaces
to enhance acoustic impedance. Examples of needles having such
surfaces include, but are not limited to, PAJUNK needles or QUINCKE
needles. The echogenic needle 10 further has a hollow needle body
16, and a proximal end 18 that may include a conventional fitting
20.
For example, the echogenic needle may generally have the
configuration of a conventional TUOHY needle except for the
echogenic features described herein. A suitable needle may be an 18
gauge, steel TUOHY needle with a HUBER tip and a TUOHY hub. Such
TUOHY needles are commercially available, with a non-insulated tip
and a plastic hub as respective integral portions of the needle.
Such TUOHY needles are available in various lengths. The needle may
also be a WEISS epidural needle having fixed wings.
Generally speaking, the echogenic needle tip may be formed from or
coated with cobalt chromium (also referred to as "cobalt chrome"),
glass or other material having a high degree of acoustic impedance.
Alternatively and/or additionally, the echogenic needle tip may
have a shape or spatial configuration that reflects an effective
amount of acoustic waves so the tip is satisfactorily visible
during sonic imaging.
Referring now to FIGS. 2A, 2B and 2C, there are illustrated
exemplary shapes for increasing the acoustic impedance of a needle
tip. FIG. 2A is a side view of an exemplary needle 22 in which a
needle body or shaft 24 terminates in a generally flat, planar
surface 26. An additional planar surface 28 can be seen at the very
tip of the needle. FIG. 2B is an illustration showing a top view of
the needle shown in FIG. 2A. In this illustration, needle body or
shaft 24 terminates in a generally flat, planar surface 26 which
provides surface area to enhance reflection of sonic energy.
Additional planar surfaces 28 can be seen at the very tip of the
needle. The needle illustrated in FIGS. 2A and 2B is sometimes
referred to as a QUINCKE needle or a needle having a QUINCKE-type
point. FIG. 2C is an illustration of an exemplary needle 22 in
which a needle body or shaft 24 terminates in a generally flat,
planar surface 26 which provides surface area to enhance reflection
of sonic energy. The needle illustrated in FIG. 2C is sometimes
referred to as a PAJUNK needle or a needle having a PAJUNK-type
point.
A useful embodiment of a needle is a WEISS epidural needle. In
particular, the needle may be a WEISS epidural needle supplied by
Becton Dickinson (BD) having fixed wings and a modified TUOHY
point. The needle may be a five-inch, 18 gauge needle and is
identified by the BD product number 405190. It should be
appreciated, however, that other types of suitable epidural needles
may also be utilized.
The needle tip and/or the needle body may be rendered echogenic by
coating the needle tip and/or a surface of the needle body with a
material that increases acoustic impedance. FIG. 3 illustrates a
cross-section of the hollow needle body 16 taken along line A-A in
FIG. 1. As can be seen in FIG. 3, a coating 32 is applied over the
needle body 34. Generally speaking, the coating can be applied over
only the needle tip and/or over portions of the needle body (e.g.,
bands). The coating may be applied by mask and dip techniques. The
coating thickness may vary depending on the coating material and
its effectiveness at increasing acoustic impedance. For example,
the coating may be 1 micrometer in thickness.
Exemplary materials that may be used to coat the needle body 16
include titanium carbide, titanium nitride, titanium aluminum
nitride, titanium aluminum carbon nitride, or similar materials may
be used. Hard, dense, amorphous non-crystalline solids such as
glass, acrylic glass--also referred to as poly(methyl
methacrylate), and hard, glassy hydrogels such as those described
in US Patent Application Publication No. US 2006/0141186 published
Jun. 29, 2006 by Janssen et al. for "Gloves With Hydrogel Coating
For Damp Hand Donning and Method of Making Same" may also be used.
The needle tip and/or needle body may be rendered echogenic by
coating the needle tip and/or a surface of the needle body with
various known echogenic coatings such as described in U.S. Pat. No.
6,506,156 issued Jan. 14, 2003 to Jones et al. for "Echogenic
Coating"; U.S. Pat. No. 7,229,413, issued Jun. 12, 2007 to Violante
et al. for "Echogenic Coatings With Overcoat"; and in U.S. Patent
Application Publication No. US 2009/0318746 A1, published Dec. 24,
2009 to Thurmond, II et al. for "Lubricious Echogenic Coatings",
the contents of which are incorporated by reference.
Referring now to FIG. 2D, there is illustrated in perspective view
a detail of an exemplary needle 22 that is rendered echogenic by
joining or incorporating echogenic elements 29 at or near the very
tip of the needle. The needle 22 has a needle body or shaft 24 that
terminates in a generally flat, planar surface 26. In this
particular example, the needle has a slight curve or bends 27 near
the tip of the needle that defines the flat planar surface 26. The
echogenic elements 29 may be glass beads, spherical particles,
grooves, indentations or other features that do not interfere with
the function of the needle. The needle illustrated in FIG. 2D is
sometimes referred to as a TUOHY needle or a needle having a
TUOHY-type point.
FIGS. 4-11 illustrate aspects of an exemplary echogenic catheter.
While the catheter may desirably be configured for controlled
delivery of a fluid across an anatomical region, the catheter may
be configured for other purposes. Generally speaking, the design of
the catheter may be similar to conventional catheters except that
the catheters are modified to include or incorporate echogenic
elements. Exemplary catheters include those described in U.S. Pat.
No. 6,350,253 issued Feb. 26, 2002 to Deniega et al. for "Catheter
For Uniform Delivery of Medication", the contents of which are
incorporated herein by reference.
Referring now to FIG. 4, the echogenic catheter 100 is composed of
an elongated tubular member 102 having a proximal end 104, a distal
end 106 and an echogenic catheter tip 108 at its distal end 108.
The elongated tubular member 102 may be an elongated tubular member
102 with a plurality of exit holes 112 in one or more portions 114
of the elongated tubular member. FIG. 5 illustrates a cross-section
of the elongated tubular member 102 taken along line B-B in FIG. 4
illustrating a porous member 116 residing within the tubular member
102. An annular space 118 may be present between the porous member
116 and the elongated tubular member 102. Alternatively, the
elongated tubular member 102 may be made of a porous membrane.
The echogenic catheter tip 108 may be a portion of a distal end 106
of the catheter 100 and may be formed from cobalt chrome, glass,
quartz, crystalline mineral, or other material having a high degree
of acoustic impedance. Another exemplary material may be stainless
steel. As shown in FIG. 6, the echogenic catheter tip 108 may
include a support 120. The echogenic catheter tip 108 may be formed
integrally with the support 120 or may be adhesively bonded
thereto. The support 120 may optionally be echogenic. Generally
speaking, the echogenic catheter tip 108 may be circular and has a
diameter such it is aligned with the outer edges of the ribs 122 of
the support 120, as shown.
Referring to FIG. 7, there is shown an embodiment in which the
echogenic catheter tip 108 incorporates reflective flakes 130,
reflective spheres 132 and/or reflective particles 136 in a carrier
matrix 138 of material such as, for example, silicone or other
suitable and compatible medical grade plastic that can be used for
the catheter tip 108. Exemplary reflective flakes 130 include gold
flakes, silver flakes or the like. Reflective spheres 132 include
gold spheres, silver spheres, glass spheres or the like. Reflective
particles 136 include gold particles, silver particles, glass
particles or the like.
Alternatively and/or additionally, the echogenic catheter tip 108
can include a very dense material incorporated into the carrier
matrix at a distal location to generate a high degree of impedance
mismatch. Dense material could also be incorporated into the
tubular member 102 in a distal location to generate a high degree
of impedance mismatch.
Appropriate selection of dense materials can create a sufficient
level of difference in the acoustic impedance of the tip 108 and/or
portion of the elongated tubular member 102 and the acoustic
impedance of the surrounding tissue to create a level of reflection
that allows visualization of the tip and/or portion of the
elongated tubular member 102 utilizing sonic imaging
techniques.
One category of relatively dense materials is radio-opaque
materials. These materials may be added to the polymer used to make
the catheter or the tip. Radio-opaque materials are those that
absorb and/or block x-rays from passing through an item. These
include iodine and barium substances, bismuth salts, tungsten, gold
metal, halogenated moieties, metal containing, optically
transparent polymers and mixtures thereof.
Halogenated moieties like halogenated diols and halogenated
di-isocyanate reactants may be used to prepare polyurethane that is
radio-opaque and desirably visually transparent. It has been found
that preparing polyurethane using trans cyclo-hexane 1,4
diisocyanate (t-CHDI) can produce a toxicologically harmless
product that is radio-opaque yet visibly transparent. More
information on this process may be found in European Patent
Application EP 0 523 928 A2 published Jan. 20, 1993 by Wagener et
al. for "Kink Resistant, Flexible, Radiopaque Polyurethane Tubing
and Catheters Formed Therefrom", the contents of which are
incorporated by reference.
The radio-opaque additive may be present in an amount between 5 and
60 weight percent, more desirably 10 and 40 weight percent or still
more desirably between 20 and 30 percent. The radio-opaque additive
may be compounded with the polymeric material from which the tube
is made in the conventional manner; e.g., barium sulfate powder is
compounded into the polymer through extrusion compounding to
produce resin pellets at the proper weight percent addition
rate.
It is contemplated that dense materials may be banded or utilized
in segments to provide contrast during sonic imaging. For example,
a band or segment may contain little or no radio-opaque additive
and another band or segment may contain at least 5 to 10 weight
percent more than the section having little or none of the
additive. It is also contemplated that both types of bands or
segments may contain a radio-opaque material which may be different
in type and/or amount, resulting in a different degree of density
for the bands or segments (e.g. tungsten in one band or segment and
barium sulfate in another band or segment). This differential in
density may allow one to discern the locations of the bands or
segments utilizing sonic imaging because of differences in acoustic
impedance.
Alternatively and/or additionally, the echogenic catheter tip may
be or may include an echogenic insert or plug 120 formed from or
coated with cobalt chrome, glass, quartz, crystalline mineral, or
other material having a high degree of acoustic impedance.
Referring now to FIG. 8, the echogenic catheter 100 may incorporate
an echogenic insert or plug 150 having a shape or configuration
that reflects an effective amount of acoustic waves so the tip or
other portion (or portions) of the catheter incorporating such an
insert is visible during sonic imaging. That is, the combination of
an appropriate shape or configuration with an echogenic material or
echogenic coating is thought to greatly enhance the acoustic
reflectivity of the insert or plug. Suitable shapes include gear
shapes (e.g., circular or cylindrical shapes having grooves,
notches and/or crenulations that provide a plurality of flat
reflective surfaces), spherical shapes, multi-faceted geometric
shapes formed by interlocking polygons (e.g., a geodesic shape).
FIG. 9 illustrates a cross-section of the elongated tubular member
102 taken along line C-C in FIG. 8 illustrating an echogenic insert
or plug 150 residing within the tubular member 102. As can be seen
in FIG. 9, the echogenic insert or plug 150 has a "star" shaped
cross section defined by spines 152 extending radially outward from
an axial or core region 154 to define a series of grooves 156 in
the echogenic insert 150.
FIG. 10 illustrates how such a feature may be incorporated in a
catheter tip 108 of the type shown in FIG. 6 such that at least a
portion of the catheter tip is echogenic. That is, the catheter
tip, the support or both may be echogenic. The catheter tip 108
includes a support 120 that may be formed integrally with the
catheter tip or may be adhesively bonded thereto. The support 120
may be generally the same as the illustrated in FIG. 6 except that
it is made of or coated with an acoustically reflective material
and configured to have a shape that is acoustically reflective. For
example, the support may have geometry similar to the echogenic
insert illustrated in FIGS. 8 and 9. Referring to FIG. 10, the
support 120 has a "star" shaped cross section that may be described
spines 152 extending radially outward from an axial or core region
154 to define a series of grooves 156. In other words, the catheter
tip may itself be echogenic and/or it may include a support that is
echogenic.
FIG. 11 illustrates a cross-section of the elongated tubular member
102 taken along line C-C in FIG. 8 illustrating another exemplary
echogenic insert or plug 150 residing within the tubular member
102. As can be seen in FIG. 11, the echogenic insert or plug 150
has a "gear" shaped or crenellated cross section defined by
protuberances 158 extending radially outward from an axial or core
region 154 to define a series of notches 160.
FIG. 12A illustrates another example of such a feature incorporated
in a catheter tip 108 of the type shown in FIG. 6 such that at
least a portion of the catheter tip is echogenic. The catheter tip
108 includes a support 120 that may be formed integrally with the
catheter tip or may be adhesively bonded thereto. In this example,
the support 120 is generally the same as the echogenic insert
illustrated in FIG. 11 and has a "gear" shaped or crenellated cross
section defined by protuberances 158 extending radially outward
from an axial or core region 154 to define a series of notches
160.
FIG. 12B illustrates another exemplary catheter tip 108 that
includes a support 120 that may be formed integrally with the
catheter tip. The support resides within the tubular member 102 and
may be secured by adhesive or by a friction fit or by other
mechanical fastening means. This catheter tip has an "hourglass"
shape and a surface that is free of crenulations or other complex
geometries. FIG. 12C illustrates another exemplary catheter tip 108
that includes a support 120 that may be formed integrally with the
catheter tip. The support resides within the tubular member 102 and
may be secured by adhesive or by a friction fit or by other
mechanical fastening means. This catheter tip has a "bullet" shape
and a surface that is free of crenulations or other complex
geometries. These relatively simple shapes are desirably made of
stainless steel but other materials having a high degree of
acoustic impedance may be used including, but not limited to cobalt
chrome, glass, or quartz.
As generally illustrated in FIGS. 8, 9 and 11, the sharp and/or
flat edges of the echogenic insert (or support) may engage the
walls of the lumen defined by the elongated tubular member 102 to
prevent the echogenic insert (or the echogenic catheter tip) from
moving relative to the elongated tubular member.
Alternatively and with reference to FIG. 13A, the echogenic
catheter 100 may incorporate an echogenic insert or plug 150 within
the elongated tubular member 102. The echogenic insert or plug 150
may be made of glass, quartz crystal or similar material and has a
generally cylindrical shape or configuration and which includes one
or more tubes or cylindrical channels 170 that passes through the
material to create a density difference that is visible using sonic
imaging. FIG. 13B is a cross-sectional view of the echogenic
catheter shown in FIG. 13A taken along line D-D. As illustrated in
FIG. 13B, the tubular member 102 incorporates an echogenic insert
150 having a cylindrical cross section and one or more tubes or
cylindrical channels 170 that passes through the material to create
a density difference that is visible using sonic imaging.
In an aspect of the invention, the echogenic catheter 100 may
incorporate an echogenic bead 172 having a spherical or spheroid
shape within the elongated tubular member 102 as illustrated in
FIG. 14A. The echogenic bead 172 may be made of glass, quartz
crystal or similar material or may be made of any conventional
non-echogenic material and provided with an echogenic coating. The
echogenic bead has a plurality of dimples 174 and may further
include rugosities or wrinkles to enhance visibility using sonic
imaging. FIG. 14B is a perspective view showing a detail of the
echogenic bead 172 highlighting the dimples and rugosities.
FIG. 15A is a cross-sectional view of an exemplary echogenic
catheter 100 illustrating voids or bubbles 176 formed in the
elongated tubular member 102. These voids or bubbles are generated
during manufacture of the catheter. The voids or bubbles may be
created by introducing a gas into the polymer that is extruded to
form the catheter. The voids or bubbles may also be created by the
extrusion process, by mixing a gas generating material with the
polymer or by other conventional techniques. Desirably, the voids
or bubbles 176 are present in the material of the elongated tubular
member 102 as illustrated in FIG. 15B and are not present at the
surface of the elongated tubular member. It is generally thought
that the voids or bubbles in the polymer material can provide
sufficiently high degree of impedance mismatch to allow
visualization through sonic imaging. It is contemplated that
materials may be mixed with the polymer to increase the density of
the polymer to further enhance the degree of impedance mismatch.
Exemplary materials are described above and may include
radio-opaque materials.
FIG. 16A is an illustration of an elongated tubular member 102 of
an echogenic catheter 100 incorporating at its distal end 106 an
echogenic catheter tip 108 having a shaft 180. The catheter tip 108
may be made echogenic generally as described above or it may
further include bands 182 of an echogenic material. It is
contemplated that the bands may be glass, quarts or other echogenic
material. It is also contemplated that the bands may be a material
having a high degree of impedance mismatch to allow visualization
through sonic imaging. FIG. 16B illustrates a detail of the
echogenic catheter tip 108 having a shaft 180 that incorporates a
band or insert 182 of an echogenic material or a material having a
high degree of impedance mismatch to allow visualization through
sonic imaging.
According to an aspect of the invention, the catheter 100 may
incorporate a metal spring 190 within the elongated tubular member
102. Generally speaking, the metal spring 190 may be used to
provide kink-resistance. The metal spring 190 may be modified to
enhance its acoustic impedance. The can be accomplished by changing
the generally round cross-section 192 of the metal spring 190 as
illustrated in FIG. 17B into a generally flat cross-section 194 as
illustrated in FIG. 17C. This generally flat cross-section 194 may
be provided in portions or alternating regions of the metal spring
and/or it may be located at the distal end 106 of the catheter. It
is contemplated that the metal spring 190 may be made actively
echogenic by being connected to a transducer that vibrates the
spring at a frequency sufficient to generate acoustic waves that
are visible through sonic imaging. Such a transducer may be, for
example a piezoelectric transducer. Other types of transducers may
include magnetostrictive transducers, electromagnetic transducers,
or laser-activated elements may be used.
The catheter 100 may be made echogenic by incorporating a removable
echogenic guide wire 200 in the catheter. The guide wire 200 may be
echogenic because it is formed it out of an echogenic material or
because of an applied echogenic coating. Alternatively and/or
additionally, an echogenic guide wire tip 202 may be added to the
echogenic guide wire 200. It is contemplated that the guide wire
200 may include a strand or additional wire 204 that is formed it
out of an echogenic material, contains an applied echogenic coating
such that it is passively echogenic. The strand or additional wire
may be configured to vibrate due to a connection with a
transducer.
Catheters frequently are manufactured with one or more metal band
or rings. In an aspect of the invention, such metal bands or rings
may be modified so they are echogenic. Referring to FIG. 19, there
is shown an illustration of an exemplary catheter 100 having a
plurality of exit holes 112 and which incorporates a first metal
band 250 near the distal end 106 of the catheter and a second metal
band 252. Referring to FIGS. 19 and 20, the bands may have a cross
section that may be described as defining spines, protuberances,
crenels or the like 254 extending radially outward from the
elongated tubular member 102. It should be noted that the
protuberances 254 are recessed in the catheter so they do not
protrude beyond outermost radial surface of the elongated tubular
member 102. Alternatively and/or additionally, the metal bands may
include grooves, indentations, cross-hatching or the like to
enhance visualization by sonic imaging techniques.
In an aspect of the invention, the metal band or metal bands and/or
any echogenic component(s) of the catheter may be configured to
provide information about the catheter. Desirably, that information
is provided during sonic imaging and is interpreted based on the
intensity or placement (or combinations thereof) of the echogenic
components. In another aspect of the invention, one or more
chart(s) or other tool(s) may be provided to allow others (e.g.,
medical professionals) to interpret the information. Alternatively
and/or additionally, the image provided during sonic imaging may be
interpreted by the sonic imaging equipment. Examples of information
about the catheter that may be provided include, but are not
limited to, exit hole placement, exit hole density, length,
diameter (or other size information), whether the catheter has an
open tip, whether the catheter has a closed tip, and the like.
The elongated tubular member 102 of the catheter 100 may be
rendered echogenic by coating an internal or external surface with
a material that increases its acoustic impedance. Exemplary
materials include titanium carbide, titanium nitride, titanium
aluminum nitride, titanium aluminum carbon nitride or similar
materials. Hard, dense, amorphous non-crystalline solids such as
glass, acrylic glass--also referred to as poly(methyl methacrylate,
and hard, glassy hydrogels such as those described in US Patent
Application Publication No. US 2006/0141186 published Jun. 29, 2006
by Janssen et al. for "Gloves With Hydrogel Coating For Damp Hand
Donning and Method of Making Same" may also be used.
The coating may be on the outside of the elongated tubular member
or the coating may be located on the interior of the elongated
tubular member. In some aspects of the invention, the coating on
the interior of the elongated tubular member may be a coating that
incorporates acoustically reflective particles in a carrier. For
example, the coating may include spherical beads of glass or other
acoustically reflective material in a carrier that binds spherical
beads to an internal surface of the elongated tubular member.
Alternatively and/or additionally, the elongated tubular member
(and/or the catheter tip) may be rendered echogenic with various
known echogenic coatings such as described in U.S. Pat. No.
6,506,156 issued Jan. 14, 2003 to Jones et al.; U.S. Pat. No.
7,229,413, issued Jun. 12, 2007 to Violante et al.; and in U.S.
Patent Application Publication No. US 2009/0318746 A1, published
Dec. 24, 2009 to Thurmond, II et al., the contents of which are
incorporated by reference. According to another aspect of the
invention, the elongated tubular member of the catheter may be
rendered echogenic by including an internal component that
increases its acoustic impedance. The internal component may be an
echogenic metal wire or even an elongated tubular coil spring
enclosed within the tubular member. The elongated tubular coil
spring may be may formed from an echogenic material, may be coated
with a material that increases its acoustic impedance, or may have
a surface that is modified with grooves, diffraction gratings,
dimples or the like to increase its acoustic impedance.
Alternatively and/or additionally, the internal component may be a
component that actively generates acoustic waves visible during
sonic imaging. Such a component may include an energy source or may
be connected to an energy source and may further include a
transducer such as, for example a piezoelectric transducer that
converts the energy into acoustic waves. Other types of transducers
including magnetostrictive transducers, electromagnetic
transducers, or laser-activated elements may be used.
In embodiments where the elongated tubular member is an elongated
tube with a plurality of exit holes or slots in a portion of the
elongated tube and an elongated porous member resides within the
tube, it is contemplated that the elongated porous member may be
made of or may include material that increases its acoustic
impedance. Examples include porous composites that may include
spherical beads of glass or other acoustically reflective material,
batts or webs formed of thermoplastic polymer fibers having
entrapped along the length thereof bubbles of a gas, a porous
matrix composed of a polymer network having gas filled closed cells
distributed in the matrix, or similar structures. An example of a
batt or web formed of thermoplastic polymer fibers having entrapped
along the length thereof bubbles of a gas can be founding U.S. Pat.
No. 6,395,215 issued May 28, 2002 to Jameson for "Method and
Apparatus for Ultrasonically Assisted Melt Extrusion of Fibers",
the contents of which is incorporated herein by reference. An
example of a porous matrix composed of a polymer network having gas
filled closed cells distributed in the matrix, or similar
structures can be found in U.S. Pat. No. 7,160,553 issued Jan. 9,
2007 to Gibbins et al. for "Matrix for Oxygen Deliver to
Compromised Tissues", the contents of which is incorporated herein
by reference.
The present invention encompasses an apparatus for performing a
nerve block procedure. The apparatus is composed of an echogenic
needle as described above and an echogenic catheter configured for
controlled delivery of a medication as described above. The
apparatus may further include an echogenic sheath. Exemplary
echogenic sheaths are described in U.S. Patent Application
Publication No. US 2009/0005774 A1, published Jan. 1, 2009 to
Fernald, the contents of which are incorporated by reference. Such
an echogenic sheath may be rendered echogenic by any of the above
described materials or techniques or combinations thereof. It may,
however, be desirable to also render the sheath echogenic to aid in
the guidance procedure and to ultrasonically verify placement of
the sheath after removal of the needle. In this regard, the sheath
may contain any manner echogenic material, such as metal threads or
flakes, formed with the sheath or subsequently added to the surface
of the sheath. In another embodiment, the sheath may be rendered
effectively echogenic by simply defining holes or perforations
through the sheath such that that the metal needle is exposed
through the perforations during the ultrasonically imaging. By
detecting axial points or sections of the needle through the
sheath, the location of the sheath is also verified.
The present invention also encompasses a system for performing a
nerve block procedure. The system includes introducing an echogenic
needle as described above in the general area of a nerve bundle,
positioning the echogenic needle adjacent the nerve bundle
utilizing sonic imaging techniques, introducing an echogenic
catheter configured for controlled delivery of a fluid as described
above through the echogenic needle, withdrawing the echogenic
needle, positioning the echogenic catheter adjacent the nerve
bundle utilizing sonic imaging techniques, and delivering fluid to
the nerve bundle through the echogenic catheter.
The above-described system for performing a new block procedure may
further include the steps of placing a sheath over the echogenic
needle prior to introducing the echogenic needle adjacent the
general area of the nerve bundle and withdrawing the echogenic
needle while maintaining the sheath in place and then advancing the
echogenic catheter through the sheath. The sheath may be an
echogenic as generally described above.
The present invention also encompasses another apparatus for
performing a nerve block procedure. This apparatus includes an
echogenic soft tissue tunneling device for creating a subcutaneous
path for placement of a catheter in a patient and an echogenic
catheter configured for controlled delivery of a medication.
Exemplary soft tissue tunneling devices are described at, for
example, U.S. Patent Application Publication No. US 2008/0086161 A1
for "Soft Tissue Tunneling Device" published Apr. 10, 2008 by
Massengale et al.; and U.S. Patent Application Publication No. US
2008/0312677 A1 for "Soft Tissue Tunneling Device" published Dec.
18, 2008 by Massengale et al.; the entire contents of each is
incorporated herein by reference.
For example, these soft tissue tunneling devices include an
elongate shaft having a rounded distal end. The distal end and/or
the elongate shaft may be made echogenic in a manner similar to the
echogenic needle and/or catheter as described above. These devices
may further include a handle secured to the shaft in which the
handle is configured to permit a user of the tunneling device to
manually manipulate the tunneling device. The elongate shaft may be
malleable so as to permit a shape of the shaft to be altered prior
to use of the tunneling device. For example, the shaft may have a
non-linear shape including, but not limited to, a curved shape.
The apparatus further includes a sheath positionable over a portion
of the shaft. The sheath has a snug fit with the shaft such that
the sheath and the shaft can be advanced together and positioned
within a body of a patient. According to the invention, at least
one of the elongate shaft and sheath are echogenic. That is, the
elongate shaft of the tissue tunneling device may be echogenic, the
sheath may be echogenic, or both may be echogenic.
According to an aspect of the apparatus for performing a nerve
block procedure, the elongate shaft of the echogenic soft tissue
tunneling device may define an interior lumen. In addition, the
tunneling device may include at least one fluid exit opening
positioned along the length of the shaft and extending from the
interior lumen to an external surface of the shaft, and an inlet to
the interior lumen to permit liquid to be introduced into the
interior lumen and administered to the patient through the at least
one fluid exit opening. The apparatus may further include a sheath
slidably positioned on the elongate shaft such that at least one of
the elongate shaft and sheath is echogenic
In another aspect of the invention, the tunneling device may
further include a retractable needle located at the distal end of
the elongate shaft. The retractable needle can be used to assist in
puncturing the skin prior to advancing the tunneling device within
the patient's body. The retractable needle can be housed within the
distal end of a needle lumen, and may be fully retracted within the
needle lumen so that the elongate shaft maintains a substantially
blunt distal end. The position of the retractable needle within the
needle lumen may be changed using any suitable method.
The present invention also encompasses a system for performing a
nerve block procedure utilizing the echogenic soft tissue tunneling
device described above. Generally speaking, the system includes the
steps of: (i) grasping the handle of an echogenic soft tissue
tunneling device for creating a subcutaneous path for placement of
a catheter in a patient--in which the tunneling device includes an
elongate shaft having a rounded distal end and defining at least
one interior lumen and at least one fluid exit opening in fluid
communication with the interior lumen; (ii) introducing the
echogenic tunneling device into the body of a patient in the
general area of a nerve bundle; (iii) positioning the echogenic
tunneling device adjacent the nerve bundle utilizing sonic imaging
techniques; (iv) withdrawing the echogenic tunneling device; (v)
introducing an echogenic catheter configured for controlled
delivery of a fluid through the subcutaneous path created by the
echogenic tunneling device; (vi) positioning the echogenic catheter
adjacent the nerve bundle utilizing sonic imaging techniques, and
(vii) delivering fluid to the nerve bundle through the echogenic
catheter.
In an aspect of the system, the echogenic tunneling device may
further include a sheath that slidably surrounds a portion of the
shaft, such that the system further includes the steps of (a)
introducing and advancing the sheath along with the introducing and
positioning of the tunneling device, and (b) withdrawing the shaft
from the sheath and leaving the sheath within the body. When such a
sheath is utilized in the system, at least one of the tunneling
device and the sheath should be echogenic.
While various patents have been incorporated herein by reference,
to the extent there is any inconsistency between incorporated
material and that of the written specification, the written
specification shall control. In addition, while the disclosure has
been described in detail with respect to specific embodiments
thereof, it will be apparent to those skilled in the art that
various alterations, modifications and other changes may be made to
the disclosure without departing from the spirit and scope of the
present disclosure. It is therefore intended that the claims cover
all such modifications, alterations and other changes encompassed
by the appended claims.
* * * * *